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| 0000768835-20-000137-index.html | 2020-09-09 16:03:57 | |
| 0000768835-20-000137.txt | 2020-09-09 16:03:57 | |
 0000768835-20-000137-xbrl.zip | 324784 | 2020-09-09 16:03:57 |
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| big-202081xex322.htm | 7321 | 2020-09-09 16:03:57 |
| FilingSummary.xml | 22765 | 2020-09-09 16:03:57 |
| Financial_Report.xlsx | 57979 | 2020-09-09 16:03:57 |
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| R37.htm | 6575 | 2020-09-09 16:03:57 |
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| R8.htm | 27944 | 2020-09-09 16:03:57 |
| R9.htm | 38204 | 2020-09-09 16:03:57 |
| report.css | 2767 | 2020-09-09 16:03:57 |
| Show.js | 1085 | 2020-09-09 16:03:57 |